Stripper for tube-punching machines



m m m Mar 20, 1923 1,448,747

L R JAMES STRIPPER FOR TUBE PUNCHING MACHINES Filed Feb. 27, 1922 2 sheets-Sheet 1 w-rwassss Mar. 2, 1923 1,448,747

L. R. JAMES STRIPPER FOR TUBE F UNCHING MACHINES Filed Feb. 27, 1922 2 51168454511664 2 4/- 4 4 F453. 4; 40 Fflfifl-n /2 I. v W

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2 lNl/ENTOR w/vwz' ssas 28 I I v Z ti Patented Mar. 26, T923.

LEWIS R. JAMES, OF EDGEWATER, NEW JERSEY, ASSIGNOR T ALUMINUM COMPANY OF AMERICA, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION 015' PENNSYL- VANIA.

STRIPPER FOR TUBE-PUNCHING MACHINES.

Application filed February 27, 1922. Serial No. 539,552.

To all whom it may concern Be it known that I, LEWIS R. JAMES, a citizen of the United States, and a resident of Edgewater, in the county of Bergen and State of New Jersey, have invented a new and useful Improvement in Strippers for Tube-Punching Machines, of which the fol lowing is a specification.

This invention relates to stripping mechanisms for presses, and particularly to a devlce for removing collapsible tubes from the plunger of an extrusion press after the tube has been formed.

The objects of the invention are to provide a device of the character referred to which is simple in construction, easy and economical to manufacture, eflicient in operation, and which is automatically actuated in response to the movements of the press. It is a special object to provide a stripper which will positively grip the formed tube to assure its removal from the punch of the press in spite of the clinging action of the tube thereto; one which will'efiect and maintain the necessary positive gripping action without injuring the tube; one which is readily released after the stripping operation has been completed; and one which is compact, easily positioned upon the press,

and does not obstruct the parts during the extrusion operation.

These and other objects of the invention will more readily appear when taken in connection with the following description and the appended claims. x

In the accompanying drawings Fig. 1 is an elevational view of the preferred embodiment of the invention; Fig. 2 a fragmentary view partly in sectionand partly in elevation showing the manner in which the gripping jaws engage the formed tube to remove it from the punch of the press; Fig. 3 a plan view of the-stripping mechanism proper together with its actuat ng mechanism; and Fig. 4 a fragmentary v1ew illustrating an alternative form of actuating mechanism.

The stripping device designated as a whole by the reference character S is adapted for W use in connection with extrusion presses employing a reciprocating plunger, that 1llustrated in the drawings COIIlPI'lSlIlg the bed plate 1 above which the side standards 2 and 3 extend, being connected at their upper extremities by the top bridge piece 4. The main operating shaft 5 of the press is suitably j ournaled in the standards 2 and 3, carries a driving gear 6 at one end, and at its intermediate portion disposed between the standards .is provided with the crank 7 for reciprocating the cross head 8 through the connecting rod 9, the cross head being guided for vertical movement in run ways 10 and 10, and provided on its lower face with a boss 11 for the reception of the punch 12.

Resting upon the bed plate 1 is the die holder 13 having a recess 14 at its central portion in which is disposed the female die member 15 with which' the punch 12 cooperates in forming the collapsible tubes 16. Upon the upper surface of the die holder in turn rests the base plate 17 of the stripper S, the dimensions of the holder 13 and the base plate 17 being preferably substantially the same, as illustrated in the drawings, and the two may be connected in any desirable manner to anchor the stripping mechanism.

Journaled in suitably spaced bearings 18, 18, mounted on the base plate 17 is a horizontal shaft 19 provided with a crank arm 20at one end and an attached gear 21 at" its opposite end. A similar shaft 22 is likewise jo-urnaled in bearings 23, 23 and carries the crank 24 and gear 25 at its opposite ends.

A pair of spaced apart bearing blocks 26 and 27 are supported upon the base plate 17, and disposed at opposite sides of the punch 12. A reciprocating gripping jaw 28 is mounted for sliding movement in the block 26 and a corresponding gripping aw 29 is similarl mounted in the block 27, the two jaws being in alignment and having semi-circular notched or cut-away portions at their abutting edges which cooperate to grip the formed tube 16 in a manner to be presently described. These cut away portions are indicated at 30, 30', respectlvely. The outer extremity of the jaw 28 is bifurcated to receive the connecting rod 31 having its opposite ends pivoted to the aw 28 and crank arm 24, respectively, and jaw 29 is likewise connected to the crank arm 20 through means of the connecting rod 32.

Journaled in a bearing 33 upon base plate 17 is a stub shaft 34 carrying the rocklng beam 35; The extremities of the beam 35 are toothedand engage the gears 21 and 25 for simultaneously actuating said gears and in turn the gripping jaws 28, 29. Pivoted at 36 to one side of theaxis of beam 35 is a link 37, the upper end of which is pivotally attached at 38 tothe lower extremity of the core 39 of a solenoid 40 supported in any suitable manner or by a frame work 41 disposed at one side of the press and out of the path of movement of the punch and cross head thereof.

Current is supplied to the solenoid 40 through conductors 42 and 42, the conductor 42 having interposed therein a switch comprising a pair, of similar contact elements 43 and 44 mounted upon the side standard 3, which are. adapted to be bridged by a segmental contact plate 45 carried by an annulus 46 of suitable insulating material fixed to the gear 6 of the press.

The mode of operation is as follows: The press, as a press, operates in the usual manner, extruding the metal of the blanks placed in the die member 15 upwardly around the punch 12 during its descent. to form the collapsible tube 16. These tubes adhere to the punch and travel upwardly therewith as it ascends, and consequently must be removed therefrom before it descends to form the next tube.

thus lifting its core 39 upwardly. Upward movement of the core 39 rocks the beam 35,

and through the-gears 21, 25, shafts 19, 22,

and cranks 20, 24,'causes reciprocation of the gripping jaws 28 and 29 towards each other. As the jaws are brought into contact they positively grip the neck of the formed tube holding it against further upward movement as the: punch continues to ascend stripping the same therefrom, the length of the plate 45 being such as to maintain the jaws in contact for a sufficient periodto effect such result. As the plate 45 moves out of contact with the members 43, 44 and the same ride upon the insulatingmaterial 46, the solenoid-is'deenergized to again permit the weight of the parts to retract the jaws and release the stripped tube, thus completing the cycle of operations.

Although the preferred embodiment of the lnventlon, as above described, comprises a solenoid to actuate the stripper S, it is obvious that various mechanical connections actuated by a movable part of the press may be employed in lieu thereof without departing from the spirit of the invent-ion. One of such alternative forms is illustrated in Fig. 4, and comprises a lever 50 fulcrumed at 51 upon the side standard 3, the upper end of the lever carrying an anti-friction roller 52 which engages a cam lug 53 attached to the gear wheel 6 of the press. The lower end of lever 50 is pivoted to a two part link 54, 55, joined by the yielding connection 56, the part 55 being in turn pivoted to the arm 57 fixed to the shaft 19 or other convenient part for rotating the shafts 19, 22. The yieldable connection 56 may be of any of the usual constructions for such purpose, the object being to assure positive gripping of the jaws 28, 29 without danger of breakage or undue strains upon the parts. As shown, the connection consists of a fork 58, fixed at one end to section 55, within which the head 59 of the section 54 has a sliding fit, a spring 60 being interposed between said head and an end plug 61. In order to maintain the ant1- friction roller 52 in contact with the cam way on the gear 6, a compression spring 62 is interposed between the upper end of the lever 50 and an abutment 63 on the side standard 3.

The operation of the form shown in Fig. 4 is as follows: The spring 62 normally moves the parts to keep the gripping jaws separated. Whenever the cam lug 53 comes into contact with the roller 52, the upper end of the lever'50 is forced towards the standard 3 and its lower end at a greater distance therefrom, moving the ,arm 57, shaft 19 and the remaining operatively connected parts to bring the jaws 28, 29 into gripping position. As soon as the inner extremities of the jaws contact, any further rocking movement of lever 50 will result in merely placing the spring 60 under tension while still maintaining the jaws in intimate contact without danger of breakage.

The cam. 53 is disposed at such angular position upon the gear 6 that the jaws 28, 29 are brought into contact to grip thetube when the punch 12 has ascended to the position shown in Fig. 2, as in the preferred embodiment, and the length of the cam lug corresponds to that of the contact plate 45, in orderto keep the jaws in gripping position for the desired period of time. As soon as the cam 53 passes the roller 52, the spring 62 again causes the parts to be moved to a position in which the jaws will be separated and ready for a repetition of the describedoperation. I

It is thus seen that the invention provides a very simple and compact apparatus for positively gripping the formed tubes to strip the same from the plunger of the press, one which is automatically operated in response to the movements of the press, which is not liable to get out of order, which is easy to repair and economical to manufacture.

I claim:

1. In combination in a forging press, a die member, a punch cooperating therewith, gripping aws normally out of contact wit-h the article formed but adapted to positively grip the same, and means controlled by the movement of the press for periodically actuating the said jaws to grip the formed article during the upward travel of the punch.

2. In combination in, an extrusion press for forming tubes, a die member, a punch cooperating therewith and to which the tube clings after being formed, reciprocating gripping jaws adapted to positively grip the formed tube upon the punch, and means controlled by the movement of the press for urging said aws finto gripping position during a portion of the upward travel of the punch.

3. In combination in an extrusion press for forming collapsible tubes, a die member, a punch cooperating therewith, and to which the formed tube clings during its upward movement, a pair of reciprocating gripping jaws normally urged out of the path of the punch, and means controlled by movement of the press for yieldingly and periodically urging said jaws into contact with the formed tube during the upward travel of the punch.

4. In combination in an extrusion press for forming tubes, a die member, a punch cooperating therewith, gripping jaws normally urged away from the plunger but adapted to grip the tube formed therearound, mechanism. for moving said jaws, a solenoid for actuating the said mechanism to cause the jaws to grip the tube, and a switch periodically closed by the movements of the press to energize the solenoid.

5. A stripper for tube forming machines comprising a base plate, a pair of oscillatory shafts jou'rnaled thereon, a. pair of gripping j aws mounted thereon and adapted to be moved toward and away from each other, operative connections between the said shafts and jaws, and means to actuate the said shafts.

6. A stripper for tube forming machines comprising a base plate, a pair of oscillatory shafts journaled thereon, a pair of aligned gripping jaws mounted for reciprocatory movement thereon, operative connections between the said shafts and jaws, and a single means for simultaneously actuating the said shafts.

In testimony whereof, I sign my name.

LEWIS R. JAMES.

Witnesses:

RAYMOND C. JAooBY, C. T. FISHER. 

